diff --git a/contrib/ChangeLog b/contrib/ChangeLog
index 1ad0aa56c7c8be99f8146a123a7dfbc33aaa1037..8d39e68a8611e0b4732fd88fb430651a09167921 100644
--- a/contrib/ChangeLog
+++ b/contrib/ChangeLog
@@ -1,3 +1,7 @@
+2015-12-06  Tobias Burnus  <burnus@net-b.de>
+
+	* download_prerequisites: Download ISL 0.15 instead of 0.14.
+
 2015-11-20  Martin Liska  <mliska@suse.cz>
 
 	* clang-format: Split content of a list to multiple
diff --git a/contrib/download_prerequisites b/contrib/download_prerequisites
index 69403301b813a2b99975570145078d5d88deb3fb..a685a1d56eb95340450bce06b0ea26a9abd41a79 100755
--- a/contrib/download_prerequisites
+++ b/contrib/download_prerequisites
@@ -48,7 +48,7 @@ ln -sf $MPC mpc || exit 1
 
 # Necessary to build GCC with the Graphite loop optimizations.
 if [ "$GRAPHITE_LOOP_OPT" = "yes" ] ; then
-  ISL=isl-0.14
+  ISL=isl-0.15
 
   wget ftp://gcc.gnu.org/pub/gcc/infrastructure/$ISL.tar.bz2 || exit 1
   tar xjf $ISL.tar.bz2  || exit 1